I'm hopeful that some of my esteemed SF colleagues can point me in the direction of a reference source for proper formal address in correspondence and speeches. Part of my job includes editing and rewriting drafts of speeches and correspondence for the president and senior executives of the company I work for. The specific problem I encountered today was a tediously fine detail regarding the use of "His Excellency." I had corrected "Excellency Bigcheese" to "His Excellency Mr. Bigcheese," having found an internet source that specified that "Your/His Excellency full name" was correct. Using the full name would have seemed stilted in the context and "His Excellency Mr. Bigcheese," I felt, was preferable. Of course, the Japanese management wanted me to back my choice of address with a solid reference, but I was unable to find a specific example of the usage I chose. Where can I find a comprehensive reference where I can chase down tedious, hairsplitting details like this?